Just as some speculation, where are the reinforcement marines coming from? And where is Foe Hammer bringing the rescued Marines, on Halo, to? It would seem like the Pillar of Autumn is too damaged to accept any marines, before it was run over by 343 Guilty Spark. Also looking at the transcripts from The Maw, Foe Hammer's Pelican was definitely not parked in the PoA. So where was Foe Hammer, and the rest of the pelicans to pick MC up and to drop MC off?

Unfortunately, the game itself provides no immediate information or mention of the area serving as the base of operations for Halo's Human inhabitants. The storyboard for this cutscene (which in my opinion is sorely missed for both background and emotional content) provides a glimpse of this makeshift home away from home.